To provide a pet opening opening/closing structure that makes it easy to use and increases convenience.SOLUTION: An opening/closing structure is provided for opening and closing an opening 21 where a pet comes in and out. The opening/closing structure includes a guide bar 31 included above and below the opening 21 and extending in the left and right directions, an outside door 32 for covering one side in the lateral direction of the opening 21 from the outside, and an inside door 33 for covering the other side in the lateral direction of the opening 21 from the inside. In the outside door 32, there is included a slide hook 34 for movably embracing a guide bar 31 from the outside along the guide bar 31. In the inner door 33, there is included a slide hook 34 for embracing the guide bar 31 from the inside. These slide hooks 34 are included in the lateral direction ends of the outside door 32 and the inner door 33, and the slide hook 34 positioned inside of left and right directions among the slide hooks of the outside door 32 and the inner door 33 is positioned between the slide hooks 34 arranged to the left or right in the door of the opposed counterpart, and thereby it is made into both left and right slide opening and closing type.SELECTED DRAWING: Figure 1【課題】使いやすくして利便性を高める、ペット用開口部開閉構造の提供。【解決手段】ペットが出入りする開口部２１を開閉する開閉構造において、開口部２１の上下に備えられ左右方向に延びるガイドバー３１と、開口部２１の左右方向の一方を外側から覆う外側ドア３２と、開口部２１の左右方向の他方を内側から覆う内側ドア３３を備える。外側ドア３２には、ガイドバー３１をガイドバー３１に沿って移動可能に外側から抱え込むスライドフック３４を、内側ドア３３には、ガイドバー３１を内側から抱え込むスライドフック３４を備える。これらのスライドフック３４は、外側ドア３２及び内側ドア３３の左右方向の端部に備えるとともに、外側ドア３２と内側ドア３３のスライドフックのうち左右方向の内方に位置するスライドフック３４を、対向する相手方のドアにおける左右に並ぶスライドフック３４同士の間に位置させて、左右両スライド開閉式にする。【選択図】図１
